The big business of bunkers

A lot can be said about bunkers. They enhance the strategy of the game. They add contrast, color and contour to a course. They enhance a target area’s visibility as well as confuse golfers about target areas. They can keep errant shots in play. Some serve no purpose other than aesthetics.

Given all that, maintaining bunkers is a big business. Most golf courses spend between 15 and 25 percent of their labor budget maintaining bunkers annually, according to a survey of superintendents and assistant superintendents conducted by Bob Randquist, CGCS, director of grounds at Boca Rio Golf Club in Boca Raton, Fla. For example, at Boca Rio, one out of every five labor hours is devoted to maintaining bunkers.

Randquist estimates it costs a minimum of $300,000 to $350,000 to maintain bunkers at championship conditions every day of the year. However, most superintendents spend between $50,000 and $125,000 annually maintaining bunkers, according to Randquist’s survey.

Normally, there are between 20 and 100 bunkers on a golf course: 40 percent of golf courses have 51 to 75 bunkers; 24 percent have 21 to 50 bunkers and 21 percent have 76 to 100, according to the survey.

Bunker size varies between less than 100 square feet to 20,000 square feet. And bunkers can be any depth; but the ideal depth depends on cost, design, sand type, degree of difficulty for playing and whether liners are used. No one says how deep bunkers should be, but the average is 4 to 6 inches, Randquist says. For example, sand depth at 1 to 3 inches has advantages and disadvantages. It packs tightly and cost less, but it’s difficult to maintain because one can’t use mechanical rakes because they would tear the liner.

Additionally, cultivating bunkers makes sand soft, and superintendent have a plethora of options for cultivator attachments, from manufacturers’ products to creative attachment made on site in the shop. Seventy-six percent of superintendents use cultivator attachments and 24 percent don’t, according to the survey.

Eighty percent of superintendents surveyed say using mechanical rakes damages bunker edges. There are times when hand-raking is better than mechanical raking, such as when the bunkers are too small or slopes are too steep. Some superintendents say bunkers just look better hand-raked. Seventy percent use mechanical rakes, and 30 percent hand-rake. Thirty-two percent rake bunkers seven days a week, 23 percent rake six days a week, 16 percent rake five days a week, 15 percent rake one to three days a week, and 14 percent rake four days a week, according to the survey.

Furrows in bunkers can be controversial. This was the case at the Memorial last year at Muirfield Village Golf Club in Dublin, Ohio. Aside from tournaments, some club members want furrows facing the pin, so when the pin changes so should the direction of the furrows.

Firmness is another element of maintaining bunkers. Superintendents can add amendments, such as granite dust, to help firm sand. It can be raked in with garden weasel, then tamped down. Packing and smoothing methods include vibratory tamp, mechanical rake sand attachments, brooms, brushes, a hose filled with sand, carpet or Astroturf.

Bunker edging is done differently too and is impacted by one’s budget. According to Randquist’s survey, 52 percent of superintendent maintain sharp edges with soil, 38 percent maintain sharp edges with grass. Additionally, 30 percent edge monthly, 21 percent edge biweekly, and 20 percent do it weekly.

Drainage can be a problem for many superintendents. Randquist says recontouring slopes might not eliminate problems like washouts. Sometimes repairing or adding drainage lines is the answer. For example, installing drainage (interceptors) around a bunker edge on the high side of a bunker prevents washouts 80 percent of the time, Randquist says.

Aside from regular maintenance, superintendents need to assure owners during a renovation or new construction that architects, who have the freedom to design any kind of bunker they want, aren’t selling the owner a bill of goods. Facts about bunkers need to be provided, and superintendents need to understand the function and design theme of bunkers.